Sometimes I wonder how many of these dangerous strings of lights have been sold via eBay and other grey import sites over the past ten years. This one is different though, as it has a rotary pattern selector (keeps last setting), so well worth exploring.
The main issues with these light strings is that they have poor electrical safety standards. Ultra thin and easily broken wire with no significant strain relief (the listing warns of a risk of breaking just while unrolling them!), loose covers over live connections on the controllers and often horribly under-rated resistors in the strings that can burn up. That seems to be more common with the shorter 100 LED strings. This one wasn't pushing the resistors too hard.
I don't recommend having these lights where kids can play with them (all kids play with fairy lights) and where pets might nibble them inquisitively.
Despite being advertised as suitable for outdoor use, these are NOT waterproof and will wick water between the wires and sleeving, resulting in a shock risk and fast failure due to DC accelerated corrosion.
Note that in this video I did have exposed live electrical connections. As always, work to your own safety level.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:- https://www.bigclive.com/coffee.htm
This also keeps the channel independent of YouTube's algorithm quirks, allowing it to be a bit more dangerous and naughty.
#ElectronicsCreators

It is that most wonderful time of the year that E goes online and treats themselves to some Jolly festive Christmas lights. Or indeed, well, these ones are purple so they'd be perfect for Halloween as well. I'll just throw the box out the way. and once again, this video is here Just to say if you've bought these, don't let pets near them.

Don't let kids near them. Just be aware that when you buy stuff like this from eBay you're not getting something that is compliant with standards. Usually there are genuinely compliant lights on eBay but but these are not. Let's get the hob up and let's do a test.

We'll actually get the anti up this time and we'll check the power consumption of these. Now these have a different controller. This is good. I shall take this apart I Don't think I've taken one of these controllers apart.

Usually it's these ones here. just the little box with a button on it that uh, defaults to its uh advertising sequence where it goes through all the patterns turn, then you have to click through to get it static. Every time. This one doesn't do that, you can set this to static all the time.

This is a double-edged sword. H These ones also come with the little sort of chinesey American a type two pin plug. Uh, this one actually comes with a UK plug which is good. so let's plug it in.

So when I plug this in, uh, it is showing as dim display. Here the lights aren't showing as flicker in the camera. That's good. Uh, 15.5 wat roughly 9 per Factor.

That's mainly cuz it's just resistor dropping the Uh current to the LEDs and uh 68 milliamps. Now this is a 500 LED set. That's an an interesting thing to know I want to see how they're wired for that? Now if I pop this open, let's see the fuse in it should be a 3 amp fuse because the fuse in British plugs is to protect the wiring. In this case, they've just chosen the biggest fuse which is a 13 amp fuse.

Let's plug it in again without the fuse and see if it lights cuz H Sometimes it does. It doesn't light without the fuse. This is good. It means the fuse is in circuit, but the fuse is the wrong one.

This is almost certainly a fake fuse as well. Let's um, get a pair of pliers and see if there's sand inside the fuse. which there should be to ensure it breaks in a controlled manner. There is sand.

Okay, that's a good start. Okay, that's that's a doubly good start. although three amp F would have been preferred. that's a UK thing.

We've got very high power uh available from wall sockets. It's basically we've got Uh 240 volts at Uh 32 amps which is the equivalent where we can Power 8 Kow from one's uh from, well, not from one socket from the circuit. typically about 3 Kow with a 30 amp fuse, right? Tell you what before I go any further. I'm going to change the fuse in this I'm going to put the 3 AMP one in one moment, please.

A more appropriate fuse has now been fitted and they're lit in their resplendant purple glow. I should actually show you the listing for these. Uh Main's plugin Christmas Fairy String Lights LED Christmas Tree Wedding Party Garden and they're available in strings of up to 1,000 LEDs I Went for the 500 LED set because the I just wanted to see how it's wired and uh, typically well, in this case, $659 The price is increasing dramatically because it goes with supply and demand. So what we have here, we've got the controller and it's interesting to note that I've come across these controllers with basically the wrapped in cling film or Saran Wrap basically the shrink wrappy types at stuff used for protecting food I Think that may be some way of getting around a regulation double insulated perhaps? I'm not really sure or to stop covers being popped off because, well, hold on.
let's do that test. Sometimes the covers in these are not clipped on well, particularly a little plate at the bottom. Well, it's not clipped on, it's just it's not fastened. Anyway, it's very used to pop off and that comes off, it exposes.

Live Connections But um, this is fairly common I wonder if that's why the other ones were wrapped in cling film, right? Okay, I'll pop that back on. It's interesting to not. This one actually has um a plug-in socket which is quite unusual. and it's got a common pin.

Uh, and it's got two switch pins so it is two channel. This is a very common sty of connector. Unfortunately, it's also shared with low voltage lights. They don't seem to use any keying.

I Recently received a product that had clearly been plugged into 240 volts when it was designed for 3 volts. So the way this is wired: H It will start off with the common wire goes through and uh, Initially, it starts off the three wires. The first wire goes to the first of the channels, then Loops out, but also has a series wire looping out and then it goes to the second one H which is the second. Channel goes in and two wires come out and you end up with five wires going along.

Uh, the common wire, the two control wires, and then the a series string of LEDs. So at some point this will change back to Three core and that's if I count the LEDs and divide by two. That's how many are W per channel. Uh, in the first few.

LEDs there should be resistors. I'm looking for the resistors. I'm not seeing the resistors. They can be sneaked in anywhere.

There's one of the resistors. it's a tiny little E W resistor. Let me just um, see if I can read that. Not sure.

Red Black? No. Brown I'm not really sure what that is. It's a three, three band color. It could go in our Direction could be brown, black, red.

I shall explore that. It's also worth mentioning that whereas on the other lights, the heat shrink is usually super wayer thin, it's actually thicker in these ones. That might be an attempt at extra safety, but it doesn't. Uh, comply with the requirement for the wires to have strain relief.
You can pull these and they usually just snap out, which is bad because then they expose live wires right? Tell you what? I'm going to explore this string of lights. I'm also going to open this box and we'll take a look at the circuit board inside it and see how it's configured one moment please. I am about to do something electrical so I feel it is prudent to start the camera just in case. Cas So I can catch horrible instance where things go wrong.

Let's stuff these wires in here and turn the power on. Oh no, the LED is just lit. That's all that happened 14 wats nothing exciting happened anticlimax, but you know, worth doing. Reverse engineering is completed with the help of a few alcoholic beverages.

The LEDs have all been counted and came up short of 500. A bridge rectifier roughed from four d has been added. I shall show you that in a moment. Out the way for these at the moment, let's take A look at the circuit board.

So I shall Focus down onto that I shall Zoom down onto it and we can explore the components on this fairly stereotypical but quite interesting version of these controllers. We have a Brid direct far we have a current limiting resistor for the power supply and a smoothing capacitor power supply. There is a shun regulator built into the chip itself, which is on a little auxiliary doter board. We have a a phase angle well zero Crossing Point detection resistor high value 2 Me we have two Thors for switching the two channels it could switch for, but they've just used two because they're cheap and uh, we have the rotary selector switch here, which is quite a sophisticated component.

It's basically got a slider ring in the middle and then it's got this outer dimple that just goes around the contacts and it's actually more sophisticated and expensive looking than I was expecting. That's quite nice. The other side of the circuit board, it looks like this: We have the AC coming on here going to the bridge direct far straight away, but one leg of the AC is taken to that uh phase phase angle and Crossing zero Crossing detection Resistor Uh, the output from the Brid direct fire goes straight to the positive output to the LEDs, but it also feeds the power to the circuitry via this 100K resistor which is going to dissipate quite a bit heat over half a watt. And there's the smoothing capacitor for that.

There's the switches. there's the r contacts. The two thers that are used PCR 406 very sensitive. H are in a position this circuit board can take four, but they've just basically left the other two positions blank.

It's very cheap and nasty. Let's take a look at the schematic. Here is the schematic: I shall Zoom down a little bit further. the AC Supply comes in and gets rectified from AC to DC full wave rectified, but UNS smoothed.

That positive goes out to feed the LEDs which are uh string of alternate LEDs and resistors. and we also have the little Supply here which is 100k current limiting resistor, the shunt regulator like a xener inside this chip here and then the smoothing capacitor 47 megar, 16 volt, I measur the voltage with nothing connected as 3.26 volts. There is this 2 megaohm resistor which is tied directly to an AC line that is most likely used to detect the zero crossing point. for dimming purposes and timing purposes in the chip.
there is the input. Instead of just being a sort of Click through the effects type thing, it actually has eight inputs. I've just drawn seven here because I ran out of room. No tell you what? No, Here's the Eth.

there we go there: I didn't run out of room and there is the uh wiper contact which goes to the Zer volt rail which wipes around those to select the pattern. You want two outputs driving the thyers directly PCR 46 sensitive Thyis and then we have roughly 80 LEDs with with just four 1K resistors interspersed with those to limit the current. and if you consider that the At LEDs let me just bring in the calculador. here: the Kink calculator.

We have the At LEDs roughly at the low current times, 2.5 volts equals 200 volt. The this is a RMS 240 volt. Supply Here the Chinese Supply is 22 Vol The 41k resistors 4 uh 4K uh will typically limit that to about 10 milliamps for the difference in voltage here, and uh, in the case of China, it would be slightly lower, but it's well within the rating which is quite nice for a change. Uh, there were in the string there were two sets of Uh 160 LEDs with Uh two channels so that was 80 plus 80 LEDs and then randomly just 7979 giving a total of 470 LEDs You cheap skates! How dare you con me out of 22 L LEDs But not to worry, it's more or less 500 LEDs right? You can drive these LEDs directly in a couple of ways without this controller.

If you just want static, LEDs Mean the controller will work for this. You can just use a Brid director for feeding LEDs directly because the way they work they have the LED string is the bulk of the voltage and then they've just got just plain resistors inter dispersed along those. But the other option you could use is a capacitor dropper. Let me draw that right now for you.

The capactive dropper has the advantage that you could add smoothing to it and limit the current. so the LED current is very low and just provides a nice ambient illumination without uh, ex limiting the LED life too much. But although having said that, the LEDs and the resistors are not being pushed too hard, which is nice. So capacitive dropper would typically be say 330 narad.

so just a wild gas could be 470 Nar or higher. it would have a discharge resist cross at 1 Meg ohm. just basically to stop getting tingle across the two Supply pins. that' be going to a bridge rectifier.

we would have a capacitor across the output. That let me just catch up here. there's output. There's output.
we have capacitor across that to provide a nice smooth DC to avoid any Flicker and we might even have a 1 Meg Ohm resistor across there. just to avoid pepy instense that would be a 400 volt capacitor. Typically 4.7 Megard is a very popular choice that would be a 1 Mega Ohm resistor and that would go out to LEDs plus and minus and that would be a nice flicker-free Supply Okay, let's take a look at the lights and I'll show you what I actually did which is basically just the incoming Supply going to a brid far and then going straight to LEDs So there is a risk of flicker, but you can judge for yourself. I shall power them up and you can see.

The bridge rectifier was made from just, uh, four discrete diodes uh 1 and4 O7s which are rated 1,000 volt. They're my go-to diode 1 amp, uh, 1,000 volts. And if I bring in a suitably shady power supply. Here here is the Shady power supply and I plug it in I reward this power supply to make it relatively safe.

Oh, things worth mentioning: The cable that came with this is copper coated aluminium. Let me just, uh, focus a more appropriate position here. Copper Coat: Uh, this. actually it's copper coated steel.

this particular one. let me strip the cable, let me strip it, and then do the flame test for you. The flame test is a very useful test to indicate if things are copper or not. although having said that, the difficulty in twisting these cores and solding them kind of suggest they are another metal coated in.

Copper Let me Zoom down this and then I shall focus on that and then I shall hold a naked flame under those and you'll see they just shrivel away instantly. And sometimes with the copper coated steel, it also creates little Sparks but in this case, they've just slumped as copper coated aluminium does and once it's fizzled out. Uh, this has maintained a certain certain flexib. The aluminum would have gone crumbly at that point.

They are crap. Don't uh, use those cables. put them in the recycling container such that they may be restored to useful materials later on. So the power is off at the moment.

I'm going to stuff these in here. Well, I hope the power is off I Did rewire after all. Here's the LEDs Let's zoom out. uh Focus down on here and we'll turn it on.

The LEDs were just light static. Uh, the power consumption is 13.5 w. um, and these will, uh, they're not being run at ridiculously high current. Um, the resistors on in series are not being overdriven which is nice.

Uh, some of the sets do overdrive the LEDs But in summary, here as you turn these off now, I'm going to leave them on cuz they're quite nice even though they're still not safe. In summary: these: LEDs the wire is single insulated. It's not very thick. It's got very thin cores that may or may not be copper.

It is no proper straing Leaf such that if anything gets snagged or pulled, these. uh, the wires can get pulled out of the Uh LED housings here which are just heat shrink which sometimes perforates and uh, exposes La connectors and these uh could potentially leave La wires hanging out. They claim these are suitable for use Outdoors they're really not for a couple of reasons. Um, Firstly, water will wake up the end and it poses a shock.
You can get a shock just by touching them because the water Bridges from the live circuitry to the Uh to your fingers basically. and also because there's DC across these LEDs at low voltage, water will Wicken through capillary action and they will rust inside and very quickly fail. They're not very good for that, so in a sense you don't want to use them around pets, you don't want to use them around young kids, You don't want to use them anywhere flammable if it's the ones that uh, have just 100 LEDs because they often overdrive the resistors in them and uh, ultimately, there, you can get better LEDs for not much more in your local suppliers like say, for instance, in America it might be Walmart In the UK it might be Asda or Tesco you can get better quality LEDs Usually with a low voltage power supply that pose much less by risk than these cheapes from eBay do and those are the ones you should buy for safety reasons. But having said that, um, if you're living living on your own and you are putting these Lights Out Of Reach and you have a fire extinguisher handy, these are probably fine.

Well, that's not a good advertisement is it? But there we go. These are generic. Chinese LEDs I Really don't recommend them. They're interesting, they're hackable, but they are Not safe.


13 thoughts on “Exploring a 500 led ebay light string with schematic”
  1. Avataaar/Circle Created with python_avatars Stefano Fantini says:

    How did you rewire the shady power supply to make it safer?

  2. Avataaar/Circle Created with python_avatars Josh Friesen says:

    The fuses in some fake or cheap products really confuse me. If you were to go down to your local hardware store and pick up a fuse, it would have sand in it, right? I don’t even think the compliant ones would cost that much. Great video.

  3. Avataaar/Circle Created with python_avatars Edwin Lipton says:

    I saw a gender confused 50-60 yr old male ferry once in front of a public convienant store. Think he thought he was peppy long stocking with his gray hair in 1" pig tails tied with pink ribbon.😂😂😂! Ferry lites might be right up his alley,, or arse!😅😅😅 Happy Spanks Giving Clyde.

  4. Avataaar/Circle Created with python_avatars Edwin Lipton says:

    Here in the States regulative compliance is just gov creating a job for those who have trouble wipping without help. The proof is in our food.

  5. Avataaar/Circle Created with python_avatars Janek says:

    Lidl currently have 580 LED string for £18, better value given I’d expect them to fulfil basic safety requirements 😅

  6. Avataaar/Circle Created with python_avatars Sven Hallgren says:

    That "Chinese-y, American-y two-pin plug" is the same one that Americans call "EU standard", isn't it?

  7. Avataaar/Circle Created with python_avatars RODALCO2007 says:

    Great video and analyses Clive, those mains wires are absolute rubbish, some copper coated iron wire. Your capacitive dropper works, I still prefer to put a 100 Ohms 2-watt inrush limiting resistor in series. The 330 or 470 nF Cap can let a large surge through when energized at the peak value 325 Volts of the mains cycle.

  8. Avataaar/Circle Created with python_avatars udhi_gn says:

    I grew up several Christmases with the old school, true 4 channel fairy light of this kind with rotary dial that keeps the same setting. Seeing a 4 channel in action is just pure nostalgia due to its distinct twinkling patterns but unfortunately nowadays the market is flooded with 2 channel ones. Lucky if you could find a 4 channel today, it's like finding a needle in a haystack. Hopefully we'll see the resurrection of the 4 channel with a safer design. Flicker-less LED design would be great bonus.

  9. Avataaar/Circle Created with python_avatars Aurelius R says:

    What you referred to at the start as a "Chinese-y, American-y" style plug — isn't that a Europlug? We definitely don't use plugs like that in North America, and China uses either a variation of our NEMA plugs, or the Aussie slanted ones.

  10. Avataaar/Circle Created with python_avatars ar corner says:

    Can you explore 5 volt led strip with 3 pin , 5v dat and gnd .
    the led modul using ic yc1166d .

  11. Avataaar/Circle Created with python_avatars Rapeanu Madalin says:

    '' and you have a fire extinguisher handy '' let's hope not a fake one…cause I have seen that they can exist…cof…ahem…somewhere…. also '' you cheap skate HOW DARE YOU con me out of 22 LED ''…that was funny…🤣they, I mean…ahem…cof..the upper rank ussualy they say that to the world when the world dare to speak some nasty truth about their empire…HOW DARE YOU

  12. Avataaar/Circle Created with python_avatars TheChipmunk2008 says:

    I love the fact you explain for our international viewers what the fuse is for.. that is a huge confusion point for people

  13. Avataaar/Circle Created with python_avatars Geoffrey Waldo says:

    Always a good day when Big Clive brings out the kink palculator😂❤

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